For over 40 years, biotechnology and genetic engineering (GE) have been used in the development of medicines and biologic agents important in protecting and augmenting human health and have been met with broad public acceptance in the health care arena. GE has also been used to improve and develop plants important to agriculture and forestry, but in these areas, it has often encountered intense opposition that has prevented or delayed the introduction of potentially useful plants. Much of the opposition to GE's application in agriculture and forestry may be driven by concerns that GE plants will serve primarily to encourage the domination of the food and wood products industries by monopolistic corporations or will be disruptive to the environment. But to conflate genetic modifications intended to promote healthy ecosystems or preserve threatened species with GE projects aimed at benefiting corporate agriculture and forestry is misleading and illogical. Further, the pervasive human disruption and damage to forest ecosystems makes it prudent to bring the best that science can offer to the protection and restoration of critical woodland denizens and broader ecosystem health. The notion that minimal human intervention in the forest environment may be the best approach ignores humanity's responsibility to help manage and protect some of the very places that have been most damaged by human intrusion. GE intended to improve forest health should be afforded the same consideration, acceptance, and support as GE intended to improve human health. These efforts should include the use of GE technology such as carefully developed transgenic trees to cure ongoing forest pathogenesis, such as the chestnut blight (Cryphonectria parasitica), which threatens to drive the American chestnut (Castanea dentata) to extinction.

Recently there have been startling reports about dramatic declines in arthropod populations, and various possible reasons for the declines have been suggested, including higher maximum temperatures due to climate change (Lister and Garcia 2018). One possible cause that has not been mentioned so far is enriched CO2 and the increased fitness and other changes in plants subject to insect herbivory that this enrichment may be causing. Since the 1950s, CO2 atmospheric concentration has risen from 300 ppm to over 400 ppm, an increase of approximately 33%. It seems possible, even plausible, that this large increase in availability of the carbon used by plants to manufacture carbohydrates is leading to changes in plants that are altering a variety of ecosystem aspects, including insect populations. It's long been known that plant growth is stimulated by CO2, and a broad acceleration in plant growth has been observed at the global level. Zhu et al. (2016) report a persistent and widespread increase of growing season integrated leaf area index over 25 to 50% of the global vegetated area during the period 1982 to 2009, whereas less than 4% of the globe shows decreasing leaf area index. These authors suggest that CO2 fertilization effects explain 70% of this observed greening trend, followed by nitrogen deposition (9%), climate change (8%), and land cover change (4%).

We examined data on fuel consumption and costs for the years 1950 through 2013, along with economic and population data, to determine the percent of U. S. gross domestic product (GDP) spent each year on fuels, including fossil fuels and nuclear ore, and the growth of the economy. We found that these variables are inversely correlated. This suggests that the availability and cost of energy is a significant determinant of economic performance. We believe this relation is consistent with analyses based on the energy return on investment (EROI) concept in that increasingly scarce, and hence expensive, fuels are a drag on economic growth. The best-fitting linear equation relating the percent of GDP (energy cost share) and year-over-year (YoY) GDP change variables suggests that a threshold exists in the vicinity of 4%; if the percent of GDP spent on fuels is greater than this, poorer economic performance has been likely. Currently, about 5% of GDP is spent on fuels; most of this is for liquids. Continued weak economic performance appears likely unless improvements in energy efficiency, on the order of a factor of 3 for liquid fuels, and/or a more rapid adoption of renewable or nuclear energy sources can be achieved, provided that the EROI of these new sources proves to be sufficiently high.

In order to assist in the identification of possible mercury (Hg) emission sources in northeastern New Jersey, this project was undertaken to delineate geographic areas in which these sources may be located. The objectives of this project were to measure gaseous elemental mercury (GEM) concentrations at a site on Staten Island, New York to the east of the putative emissions source and analyze these results with those obtained by the NJDEP at their air monitoring site (ELAB) in Elizabeth, New Jersey. Additional local measurements were to be obtained near possible emission sources. From September 30, 2011 to September 3, 2012, GEM data were collected for more than 200 days at the Staten Island site. Together with wind speed and direction data from the NOAA Bergen Point West Reach naval observatory station these measurements were analyzed and transport trajectories of GEM in the region were determined. GEM concentration and wind direction data from the ELAB site for the same period of time were also analyzed. Local measurements of GEM in the area were limited by access to appropriate sites and difficulties maintaining stable calibration of the portable Hg analyzer. Directional analysis of the number frequency and concentration-weighted distributions of GEM peaks with concentrations >4 ng m at the ELAB site revealed a single source located to the south of the sampling site (bearing 173.4°). Similar analysis of GEM results for the Staten Island site revealed two possible sources, one to the west (bearing 280.5°) and a second to the southwest (bearing 213.8°). The intersections of the two Staten Island transport trajectories with the ELAM trajectory delineate two possible GEM source areas. The first is centered in Rossville, NY on Staten Island (40.5514 N, 74.1947 W) and the second near Pralls Island in the Arthur Kill along the eastern border of Linden, NJ (40.6119 N, 74.2039 W). Temporal analysis of GEM peaks for the three source directions indicates that the eastern Linden source may contribute more GEM to elevated measurements recorded in Elizabeth than the Rossville source. mercury, reactive gaseous mercury, and particulate mercury, were observed at Elizabeth and New Brunswick, New Jersey during the period of 2003 to 2006 (Aucott et al., 2009). No relationship between the occurrence of episodic spikes in atmospheric mercury and meteorological conditions (season, temperature, precipitation) has been found, and such events are likely related to local industrial activities. Similar spikes observed in New York City were also attributed to local anthropogenic sources (Carpi and Chen 2002). In Elizabeth, elevated atmospheric mercury concentrations appear to correlate with a southerly wind direction (Aucott et al., 2009), indicating a possible location of a mercury point source, but no known source of mercury

An analysis of the energy return on investment (EROI) of natural gas obtained from horizontal, hydraulically fractured wells in the Marcellus Shale was conducted using net external energy ratio methodology and available data and estimates of energy inputs and outputs. Used as sources of input data were estimates of carbon dioxide and nitrogen oxides emitted from the gas extraction processes, as well as fuel‐use reports from industry and other sources. Estimates of quantities of materials used and the associated embodied energy as well as other energy‐using steps were also developed from available data. Total input energy was compared with the energy expected to be made available to end users of the natural gas produced from a typical Marcellus well. The analysis indicates that the EROI of a typical well is likely between 64:1 and 112:1, with a mean of approximately 85:1. This range assumes an estimated ultimate recovery (EUR) of 3.0 billion cubic feet (Bcf) per well. EROI values are directly proportionate to EUR values. If the EUR is greater or lesser than 3 Bcf, the EROI would be proportionately higher or lower. EROI is also sensitive to the energy used or embedded in gathering and transmission pipelines and associated infrastructure and energy used for their construction, energy consumed in well drilling and well completion, and energy used for wastewater treatment.

Lead is a well-known pollutant with documented toxicity. Lead-containing weights used to balance motor vehicle wheels are regularly lost from vehicles and enter the environment. Lead weights deposited on roadways in the vicinity of Trenton, NJ were gathered and measured from February 2006 to January 2009. Measurements included loss of mass from specific weights exposed to traffic. Extrapolation of the results to the entire state suggests that approximately 12 tons per year of lead in the form of wheel weights are deposited on New Jersey roadways, and that approximately 40 kg of lead enters the environment in the form of small particles formed from the abrasion and grinding action of traffic on weights deposited on roadways. This quantity of small particles is much less than the approximately 60 tons per year of lead estimated by an earlier study to enter New Jersey in precipitation, some of which may result from the combustion of leaded aviation fuel. The quantity is also likely small compared with the fluxes of lead into the environment that still continue from leaded paint and with the residue of finely dispersed lead from historical uses of leaded gas in motor vehicles that remains in the environment. The quantity of lead released to the environment in the form of wheel weights appears likely to decline in the future because of legislation, voluntary phase-outs by manufacturers, and new trends in wheel technology.

Lead is a well-known pollutant with documented toxicity. Lead-containing weights used to balance motor vehicle wheels are regularly lost from vehicles and enter the environment where they are ground into small particles by traffic, thus releasing small particles of lead to the environment and potentially contributing significantly to human exposures. The purpose of this study was to measure the quantity and to assess the form and fate of lead that enters the environment from wheel weights, and to estimate the exposure potential that this lead might represent as compared with other measured and estimated inputs of lead to the environment. This study found that approximately 12 tons per year of lead in the form of wheel weights are deposited on New Jersey roadways, but that only approximately 40 kg of this enters the environment in the form of small particles that are likely to result from the abrasion and grinding action of traffic. This study indicates that, relative to other sources, the amount of lead dispersed in the form of small particles to the environment from wheel weights is small. Further, the quantity of lead released via wheel weights appears likely to decline because of state-level legislation, voluntary phase-outs by manufacturers, and new trends in wheel technology.

Replacing incandescent bulbs with compact fluorescent light bulbs (CFLs) saves energy. This saving, coupled with the longer life of CFLs in most applications, could be expected to lead to rapid acceptance of the bulbs. However, use of CFLs in the United States, while growing, and higher in some regions such as California and the Northwest, is still relatively low. Various reasons exist for the poor acceptance of CFLs so far, including higher initial cost, unsuitability for certain uses (e.g., dimmable fixtures), and, in some cases, undesirable light quality. One concern that has been expressed is that the bulbs contain mercury. Mercury's toxic properties are well known, and its use in products and release to the environment during these products’ life cycles has contributed to widespread mercury pollution. A material flow analysis, carried out with the use of data available in New Jersey, has been instructive in placing mercury aspects of CFLs in perspective with other uses and releases of mercury. Because of certain useful properties, mercury and mercury compounds have been intentionally added to products for years, including pharmaceuticals, agricultural chemicals, dry-cell batteries, and paints. Although these uses have been essentially phased out, other uses continue, including chlor-alkalai production, switches and electrical apparatus, dental amalgam, and, as discussed here, fluorescent light bulbs. Mercury also is present in coal, with a typical concentration in the vicinity of 0.1 parts per million (ppm). And, as a naturally occurring element, it is generally present at measurable levels in soils and organic material. In the case of CFLs, the quantity of mercury contained and likely to be released to the environment over varying time scales corresponding to stages in the product's life cycle should be compared with the benefits of the bulbs in terms of energy savings and also in terms of lowered mercury releases from electricity production. A paper by Eckelman and colleagues (2008), based on a spatially differentiated analysis, indicates that the reduction of mercury pollution by end-of-life treatment of CFLs could be significant. A material flow analysis (MFA), carried out with the use of data available in New Jersey, has been instructive in placing mercury aspects of CFLs in perspective with other uses and releases of mercury. In this MFA, we used several of the data and assumptions as specified by Eckelman and colleagues (2008). Such an analysis suggests that, for the United States as a whole, widespread use of CFLs would add a relatively small quantity to the mercury pollution burden, and this quantity would be more than offset by reduced mercury emissions from electric power production. (Not explored by this analysis is the possibility that there may be other mercury-related issues associated with CFLs, such as exposures to mercury vapor if bulbs are broken in poorly ventilated environments where humans or pets are present for extended periods.) The first step in this analysis was an assessment of the overall flow of mercury to disposal facilities. A new method, based on the concentration of mercury in municipal solid waste (MSW) incinerator ash, was used. Residual ash and solid waste data were obtained from the monthly summary reports submitted to the New Jersey Department of Environmental Protection (NJDEP) from two MSW incinerators in New Jersey. Total MSW incinerated, percent ash moisture, total ash residue, and total concentrations of mercury in the ash were tabulated on a monthly basis for the period 1995–2007 for one incinerator, and from 2004–2007 for the other. Also submitted to NJDEP as part of air pollution permits for these facilities are quarterly stack test data showing mercury content in the exhaust gas. Mean monthly total content of mercury of the ash was determined and compared with the total amount of waste incinerated. The quantity of mercury in the exhaust gas was added to the quantity of mercury in the ash to arrive at the total amount of mercury in the incinerated waste. The estimated mean concentration and 95% confidence limits for mercury concentration of the MSW processed by the two incinerators was 2.6 ± 0.2 ppm and 0.9 ± 0.2 ppm (Aucott et al. 2009). The incinerator with the higher concentration of mercury in its MSW receives about six times as much MSW as the other incinerator, and it receives a higher proportion of industrial waste. Based on these two facilities’ data, a national average MSW mercury content is likely to be in the general range of 1 to 2.5 ppm. About 250 million (short) tons of MSW are generated yearly in the United States, and about 170 million tons of this are either landfilled or incinerated. Modern incinerators can be expected to capture 95% or more of the mercury in incinerated waste through the use of activated carbon in their emission control systems. This captured mercury, bound to carbon, is transferred to the ash, which goes to landfills. Assuming a mean concentration of 1.5 ppm, these 170 million tons of MSW disposed would represent 250 tons of mercury sent to landfills in the United States each year. Interestingly, this quantity is similar to the amount of mercury used in products in the United States in recent years,1 and much less than the quantity used in products earlier, which was in the range of 1,500 to 2,000 tons annually from the 1950s through the 1980s. The fate of mercury deposited in landfills must be considered. Although no data exist on performance of landfills for periods greater than 50 years, available data indicate that releases of heavy metals from landfills are low (Aucott 2008). Based on review of landfill vent stack test data and measurements of leachate concentrations, the New Jersey Mercury Task Force estimated that landfills in New Jersey emit in the range of 10 kilograms (kg) mercury per year to the air (NJDEP 2002). Apportioning this quantity to the entire United States suggests a yearly mercury air emission from landfills in the range of 0.3 tons. Landfills also can be expected to emit mercury in the form of leachate. Data suggest that the mean concentration of mercury in landfill leachate is in the range of 7 micrograms per liter (μg/l).2 Using this value and assumptions about quantities of landfill leachate suggests that the yearly U.S. emission of mercury to the environment in the form of landfill leachate is in the range of 2 tons. These estimated emissions from landfills should be compared with the estimated 125 tons of mercury estimated to be released to the air yearly by industrial and other sources in the United States. The USEPA estimates that approximately 50 tons of this total comes from coal combustion. It should be noted that mercury released from landfills is coming from the entire pool of mercury deposited in those landfills, which, because mercury has been used in products since at least the beginning of the 20th century, is likely to be on the order of 50 or more times the current yearly input of mercury to these disposal sites. How much could CFLs contribute to the flux of mercury to landfills, and to the overall emission of mercury to the environment? CFLs are reported to contain an average of 5 milligrams (mg) of mercury. A new voluntary standard adopted by the National Electrical Manufacturers Association (NEMA) in 2007 limits the mercury content of CFLs to 5 mg (Eckelman et al. 2008), and many bulbs are reported to already contain less. The United States passed the Energy Independence and Security Act of 2007, which establishes a lighting efficiency standard sufficiently high that it is likely to phase out most incandescent bulbs by 2014. Eventually, with the assumption that most of the several billion incandescent bulbs currently in use are replaced by CFLs, and that the lifetime of CFLs is in fact significantly longer than that of incandescent bulbs, 300 million or more CFLs might be sold per year in the United States, and this many might eventually be discarded yearly as well. At 5 mg each, 300 million bulbs would add 1.5 tons, about 0.6 percent, to the total amount of mercury deposited in landfills each year. Their relative contribution to the total pool of mercury in landfills, and hence to the emissions of mercury from these landfills, would be much lower however, since, as discussed above, the total quantity of mercury in landfills is likely to be much more than the current annual deposition. Even if it is mostly fresh inputs of mercury that contribute to emissions from landfills, CFLs would contribute less than 1% of an emission that totals only 2 to 3 tons per year. What about breakage of CFLs while in use, or while in the disposal stream? Broken CFLs, if they behave similarly to broken fluorescent tubes, can be expected to release perhaps as much as 40% of the mercury they contain in a two-week period, at the end of which period they would very likely be entombed in a landfill (Aucott et al. 2003). A small amount of mercury can be expected to escape from emission controls at incinerators and be released to the air from incinerated bulbs. Altogether, discarded bulbs might release as much as 0.75 tons to the air, about 0.6 percent of the yearly air emission in the United States. If at some point it proves feasible to recycle a significant percentage of discarded CFLs and so recapture the mercury they contain, the quantity released would be smaller still. In addition, saving energy reduces emissions of carbon dioxide, a major greenhouse gas. Reductions of emissions of such gases are important, perhaps essential, for future well-being. And, by saving energy, CFLs should contribute to lower emissions of mercury by power plants. It is estimated that residential buildings account for about one third of the nation's electricity use, and that lighting accounts for about 10% of residential energy use. Residential lighting thus represents about 3% of the nation's electricity use. Approximately 50% of U.S. electricity is produced by coal combustion, which, as noted above, emits about 50 tons of mercury per year. At 3% of the total electricity use, residential lighting thus would be responsible for about 1.5 tons of the mercury released by coal combustion. CFLs use about one fourth of the electricity used by an incandescent bulb of similar brightness. So, if they universally replaced incandescent lighting, they might cut this 1.5 ton release to less than 0.5 tons, a reduction of greater than 1 ton of emissions per year.3 This is more mercury than these bulbs would release to the environment, even if it is assumed that a large portion of them break before they are sequestered in a landfill or recycled. Based on this materials-accounting analysis, CFLs, even if used much more widely than presently, are not likely to contribute significantly to the anthropogenic releases of total mercury in the environment. If these bulbs are widely adopted, their net effect could be a modest lowering of such releases. Michael Aucott, PhD, is a research scientist in the Office of Science in the New Jersey Department of Environmental Protection in Trenton, New Jersey.

We present a mid to late Holocene sea-level record derived from drilling the New Jersey coast that shows a relatively constant rise of 1.8 mm/yr from similar to 5000 to 500 calibrated calendar years before present (yrBP). This contrasts with previous New Jersey estimates that showed only 0.5 mm/yr rise since 2000 yrBP. Comparison with other Mid-Atlantic sea-level records (Delaware to southern New England) indicates surprising uniformity considering different proximities to the peripheral bulge of the Laurentide ice sheet, with a relative rise throughout the region of similar to 1.7-1.9 mm/yr since similar to 5000 yrBP. This regional sea-level rise includes both: 1) global sea-level (eustatic) rise: and 2) far-field geoidal subsidence (estimated as similar to 0.8-1.4 mm/yr today) due to removal of the Laurentide ice sheet and water loading. Correcting for geoidal subsidence, the U.S. east coast records suggest a global sea-level (eustatic) rise of similar to 0.4-1.0 mm/yr (with a best estimate of 0.7 +/- 0.3 mm/yr) since 5000 yrBP. Comparison with other records provides a best estimate of pre-anthropogenic global sea-level rise of <1.0 mm/yr from 5000 until similar to 200 yrBP. Tide gauge data indicate a 20th century rate of eustatic rise of 1.8 mm/yr. whereas both tide gauge and satellite data suggest an increase in the rate of rise to similar to 3.3 mm/yr from 1993-2006 AD. This indicates that the modem rise (similar to 3.3 mm/yr) is significantly higher than the pre-anthropogenic rise (0.7 +/- 0.3 mm/yr). (C) 2008 Elsevier B.V. All rights reserved.

Heavy metals are present in a variety of products and can be released to the environment during product life cycles. The concentration of metals in municipal solid waste (MSW) reflects the amount of metals in products and is directly related to the amount of metals transferred to disposal sites. Measured monthly mean concentrations of cadmium, lead, and mercury in the ash from May 1995 through October 2007 at the Essex County, NJ incinerator and from May 2004 through November 2007 at the Warren County, NJ incinerator were used, along with air emissions data for mercury, to estimate the content of these metals in MSW. Estimated mean concentration and 95% confidence limits for cadmium in MSW at the Essex and Warren facilities, respectively, were 17.4 ± 0.1 and 10.1 ± 1.2 ppm. For lead, the corresponding values were 408 ± 41 and 239 ± 42 ppm, and for mercury, they were 2.6 ± 0.2 and 0.9 ± 0.2 ppm. A trend of increasing cadmium concentrations was found at both facilities. No change vs. time was observed in lead concentrations. Mercury concentration was found to be decreasing over time at the Essex facility.

Two and a half years of data of ambient concentrations of elemental mercury (Hg(0)), reactive gaseous mercury (RGM), and particle-bound mercury (Hg(p)) were collected at measurement sites at Elizabeth, New Jersey and New Brunswick, New Jersey with Tekran sampling units. The data were processed, summarized, and analyzed from a variety of perspectives. Data quality control and quality assurance procedures are described. Wind direction and wind speed data for each of the sites were also collected. Significant temporal variations in concentrations of all three species were observed. Some significant directional variations were also seen. The sporadic nature of many of the temporal variations is consistent with and could reflect highly variable emissions patterns from anthropogenic mercury sources. Overall mean concentrations of all species were determined. These were, for Hg(0), Hg(p), and RGM respectively; 2.25 +/- 0.04 nanograms per cubic meter (ng/m(3)), 8.21 +/- 0.39 picograms per cubic meter (pg/m(3)), and 8.93 +/- 0.31 pg/m(3) (arithmetic means and 95% confidence intervals) at Elizabeth, and 2.15 +/- 0.02 ng/m(3), 10.73 +/- 0.45 pg/m(3), and 6.04 +/- 0.30 pg/m(3) at New Brunswick. Mean concentrations were determined for 16 different sectors representing wind directions. The impact of one known large source is suggested by these data. Reasons for some directional variations are not apparent and suggest a need for further investigation.

Atmospheric deposition is an important source of a number of contaminants to the environment. The New Jersey Atmospheric Deposition Network (NJADN) was a collaborative research and monitoring effort between Rutgers University and the New Jersey Department of Environmental Protection (NJDEP). The objectives of the project were to quantify current concentrations and deposition fluxes of targeted contaminants and assess their spatial and seasonal trends, and, to the extent possible, to determine the importance of atmospheric deposition relative to other inputs. Contaminants measured included PCBs, PAHs, certain organochlorine pesticides, heavy metals, nutrients, and organic and elemental carbon particles. NJADN results have established baseline levels of the organic contaminants in the gas, particle, and precipitation phases and of the metals, nutrients, and organic and elemental carbon in the particle and precipitation phase. These baseline levels will be useful in the evaluation of long-term trends and determining the effectiveness of pollution control efforts. John R. Reinfelder, Lisa A. Totten, and Steven J. Eisenreich Michael Aucott

Anthropogenic emissions of trichloromethane (CHCl3, chloroform) in 1990 have been estimated with a variety of methods specific to the source category. The largest source category for CHCl3 was found to be pulp and paper manufacturing, responsible for an estimated 30±8 Gg yr−1 reactive chlorine in the form of CHCl3. Water treatment of various types was estimated to contribute another 19±12 Gg. Manufacturing facilities of products other than pulp or paper and other relatively minor sources were estimated to emit an additional 13±5 Gg yr−1, for a total of 62±25 Gg yr−1 reactive chlorine in the form of CHCl3. The global flux of chlorodifluoromethane (HCFC‐22) is well characterized from industrial and regulatory data to have been 195 Gg in 1990, equivalent to 80±0.6 Gg yr−1 as active chlorine. The fluxes of reactive chlorine from CHCl3 and HCFC‐22, distributed globally in a 1° latitude times 1° longitude grid, revealed areas highest in emissions.

Much if not all of the chlorine present in fossil fuels is released into the atmosphere as hydrogen chloride (HCl) and chloromethane (CH 3 Cl, methyl chloride). The chlorine content of oil‐based fuels is so low that these sources can be neglected, but coal combustion provides significant releases. On the basis of national statistics for the quantity and quality of coal burned during 1990 in power and heat generation, industrial conversion and residential and commercial heating, coupled with information on the chlorine contents of coals, a global inventory of national HCl emissions from this source has been constructed. This was combined with an estimate of the national emissions of HCl from waste combustion (both large‐scale incineration and trash burning) which was based on an estimate of the global quantity released from this source expressed per head of population. Account was taken of reduced emissions where flue gases were processed, for example to remove sulphur dioxide. The HCl emitted in 1990, comprising 4.6 ± 4.3 Tg Cl from fossil fuel and 2 ± 1.9 Tg Cl from waste burning, was spatially distributed using available information on point sources such as power generation utilities and population density by default. Also associated with these combustion sources are chloromethane emissions, calculated to be 0.075 ± 0.07 Tg as Cl (equivalent) from fossil fuels and 0.032 ± 0.023 Tg Cl (equivalent) from waste combustion. These were distributed spatially exactly as the HCl emissions, and a further 0.007 Tg Cl in chloromethane from industrial process activity was distributed by point sources.

The identified emissions of the title compounds come predominantly from their use in industrial and commercial processes. Trichloroethene and tetrachloroethene have also been found as byproducts of gasoline and coal combustion; these sources were also considered but shown to be insignificant compared with industrial releases. Global emissions during 1990, amounting to 0.241±0.013 Tg of trichloroethene, 0.366±0.020 Tg of tetrachloroethene, and 0.583±0.032 Tg of dichloromethane (0.195±0.010, 0.313±0.017, and 0.487±0.027 Tg as chlorine, respectively) have been assigned to individual countries and thence to a 1° latitude × 1° longitude grid based on a combination of three data sets: regional sales data that were available on a continental scale; economic activity in the form of national Gross Domestic Products; and the population distribution within each country. For those countries where they were available, data for the quantities and locations of reported emissions were also incorporated. Uncertainty in the distributed emissions is ±4% relative to countries with the largest emissions. The results, which are complementary to the marine fluxes and releases from biomass burning reported by Khalil et al [this issue] and Lobert et al [this issue], respectively, are recorded here as maps and are also available from the Global Emissions Inventory Activity web site at http://groundhog.sprl.umich.edu/geia/rcei. While the industrial regions of North America, Europe, and Japan are the largest sites of anthropogenic emissions, there are also significant sources in the developing nations of Asia; in contrast, anthropogenic emissions within the southern hemisphere are much smaller and more widely dispersed. The total emissions of dichloromethane appear to match the observed atmospheric concentrations, but about 25% of the flux of tetrachloroethene calculated from observations remains unaccounted, and significant extra emissions of trichloroethene are necessary to effect a balance. The known sources have been examined thoroughly in this work, and so it is reasonably certain that the additional emissions are not a deliberate result of human activity; however, there is no means of discriminating their origin unequivocally, and the missing quantities may be inadvertent byproducts of anthropogenic activities.